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1 of 1 people found the following review helpful:
1.0 out of 5 stars
Good for DIY parts only; do NOT buy this for a kid!, November 22, 2007
Durability:2.0 out of 5 stars Fun:1.0 out of 5 stars Educational:1.0 out of 5 stars
I will go into detail about the good and bad points of this telescope, but if you just need a quick answer: forget it. You will not see anything through this telescope as shipped. All it will accomplish is to make the recipient hate astronomy. The scope does include some good parts, but it is not a useable instrument without a considerable amount of work.
GOOD POINTS:
The mirrors on this telescope are excellent. I pulled the mirrors out of mine and remounted them in a PVC truss-tube design to make a collapsible travel telescope, and the views are stunning considering the aperture is only 3 inches. Both mirrors have a full set of collimation screws, and the secondary mirror is on an adjustable 3-vane spider. (Hint: if all that sounded like gibberish to you, you lack the experience necessary to rebuild this telescope into anything useful.)
The mount is surprisingly sturdy. It's an aluminum alt-az mount, which usually means lightweight and shaky, but in this case the telescope is light enough, and the mount heavy enough, to provide reasonably stable views.
The 6x30 finderscope is all plastic and usually that means trouble, but mine actually works and provides good images. Maybe I got lucky.
BAD POINTS:
The focuser is terrible. It's an all-plastic rack and pinion job, and the travel is extremely rough--the focusing equivalent of bouncing over a severely washboarded dirt road. The drawtube is so loose that when it is racked out you can move it from side to side by almost half a centimeter! The final insult, though, is that to make the plastic focuser look like metal they painted it silver--inside and out. That means that when you look through the focuser you get all kinds of horrible reflections from inside the focuser tube!
As bad as the focuser is, it does at least function, which is more than I can say for any of the included eyepieces and the "Barlow". Looking through the included eyepieces is like looking through a very blurry fish-eye lens. There is a very small spot in the center of the field of view that can be brought into focus with some patience and some effort, but it is surrounded by a very wide donut of increasing blur. You cannot fit the moon into the non-blurry area even on the lowest available power. The 167x magnification touted on the box is a joke--even with excellent mirrors, maximum useful magnification is about 1.5 times the aperture in mm, which in this case means about 100x. And indeed the mirrors here are good enough to go up to 100x with good eyepieces--I know, because I have done that with the remounted optics. But all of the stuff above how bad the included eyepieces are only applies to the 20mm e.p. The 12 and 9mm ones are so bad that I cannot get an image to form at all. I tried using the (all-plastic!) "Barlow" lens with good eyepieces on the remounted mirrors, and I couldn't see a thing. And this is a setup (good eyepieces, remounted mirrors) that turns in razor-sharp images without the "Barlow".
HOW TO FIX IT UP:
If you didn't want to pull the mirrors and remount them, you could turn this into a functional instrument by taking off the entire focuser and throwing it and the included eyepieces into the trash (or into your junk optics drawer, in case you want to noodle around with them later). Then you could build a helical focuser out of plumbing parts and attach it to the tube with screws or some Automotive Goop. You'd still need to buy one or more decent eyepieces, or pull an eyepiece out of an old pair of binoculars. All that work will require an afternoon, about ten bucks in parts--and some experience building telescopes.
VERDICT:
As a bag of parts for an amateur telescope maker, this is an okay product if you can find it on sale (mine was). It is not a useful instrument on its own. It is a real shame because it is about 95% of a potentially great telescope--decent tripod, solid alt-az mount, nice tube, excellent mirrors, and fully collimatable mirror mounts. But it all goes down the drain in the last four inches, with the extremely bad focuser and the atrocious eyepieces. So ironically the product is completely wrong for the targeted demographic (kids), and only useful to experienced telescope makers who are unlikely to pick it up in the first place. I think it is morally wrong to market such a useless piece of junk to kids, especially under the guise of science and education, and I am ashamed of the National Geographic Society for putting their name on this abomination. Unless you already have some idea of how you are going to rebuild it, avoid this thing like the plague.
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